Perhaps you are right, I'm not familiar enough with the C8 suspension to know all it's nuances. But, in general, when you lower a car you move the suspension closer to its upward travel stops and further away from its downward stops. So it will have less travel in the upward direction and more travel in the downward direction. I.e., if you had enough adjustment threads you could lower the car until the suspension was resting on its stops. That is one of the reasons it is better to increase the spring rate when you lower a car. The best way is to relocate the suspension attach points to keep the geometry correct during full travel. I'll let someone more familiar with the C8 suspension chime in.